Thoracic rotation, position

The challenge for spinal artery CTA is to provide sufficient arterial enhancement but to scan before arrival of contrast medium in the venous system. An ROI of the bolus tracking system placed in the ascending aorta might be affected by inflow artifacts of the SVC and may result in a mistimed early scan. Therefore, placement of the ROI in the aortic arch or descending aorta is recommended. In the presence of aortic dissection, caution should be taken that the ROI is not too big or positioned in the false lumen or across the dissection membrane, respectively. In these cases, manual start of the scan should be considered. The Hounsfield unit threshold should be around 100 HU above baseline. Scan start is usually delayed by time for table movement (<3 s), which is usually right above the origin of the vertebral arteries. An additional scan delay of 3 s is recommended for scanners with equal to or more than 16 rows and rotation time equal or less than 0.4 s. Hounsfield unit values of attenuated blood in the thoracic aorta should never be lower than within the pulmonary trunk. 

The terminology reflects the fact that the vertebra assumes the position of its freedom of motion. T7 ESrRr indicates that the seventh thoracic vertebra is extended, side-bent to the right, and rotated right on T8. In this case, the seventh thoracic vertebra is restricted in the motions of flexion, side-bending to the left, and rotation to the left. 

Spinal somatic dysfunctions are classified as type I or type II dysfunctions. Type I dysfunctions follow Fryette s first principle of physiologic motion, which states that when the vertebrae are side-bent from a neutral position, rotation will occur in the opposite direction from the side-bending. These are group curves in the thoracic or lumbar regions involving more than... 

For example, on palpation, the transverse process of the fourth thoracic vertebra is more prominent posteriorly on the right. Is it part of a somatic dysfunction complex involving three planes and six motions on a helical axis The vertebra is placed into a position of flexion. The right transverse process becomes more prominent posteriorly. It is assumed that this has happened because there is a barrier preserrt to the motion of flexion, and the vertebra is resporrding according to the rale of the effect of resistance on linear motion. That is, on meeting this flexion barrier, the vertebra turns away from and arotmd it in the direction of allowable freedom of motion, or right rotation. 

Rotoscoliosis testing. The diagnosis of type I dysfunctions is based on detecting three or more adjacent vertebrae whose positional rotation is greatest in neutral. Testing is performed separately for the upper and lower thoracic regions. 

Figure 39-1 shows the locations of the anterior tender points for the thoracic spine. All anterior tender points are treated with flexion as the major movement in positioning. Fine-tuning of the position will be by side-bending and/or rotation. 

The occipital atlantal junction was restricted in flexion and extension but symmetric and sidebending in rotation. There was tenderness along the superior nuchal line bilaterally. There was a mild thoracic and lumbar flattening with a decreased excursion of the diaphragm and rib structures on inhalation. The left first rib was restricted with the rib in the elevated position. The thoracolumbar junction was tender to palpation in the midline and bilaterally across the... 

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